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avoid such speculations when another option exists. Shoemaker offers pure dispositionality as
an alternative. Without taking into consideration the idea that qualitative and dispositional
properties are the same (which is admittedly a surprising identity (Heil 2003: 218)), a pure
powers view of properties does look like the most viable theory.
3. Pure Dispositionality
Many metaphysicians have noted problems with pure dispositionality, usually assuming that
this position stands or falls with a purely relational account of substance (for example, see
Heil 2003: 102). Martin is among the few who do not assume that pure dispositionality
stands or falls with a relational account of objects. Instead, Martin argues that a purely
dispositional account of properties leads to two regresses. The first comes from properties
reducing to dispositions, the second from the manifestation of dispositions reducing to
dispositions. I will briefly outline his reasons for thinking that two regresses follow.
First, let us examine what a pure powers account of properties says about alleged ‘qualitative
properties.’ On a pure powers account of properties, a property that appears qualitative (e.g.
length) reduces to a capacity (e.g. being capable of being measured at six inches), but this
capacity reduces to a disposition “for the formation of other capacities” (Martin 2008: 63).
Now, these capacities, which are the reduction of a disposition, also reduce to the formation
of other capacities. The same holds with a dispositional property, which is a capacity. This
capacity reduces to a disposition “for the formation of other capacities” (Martin 2008: 63).
These capacities, which are the reduction of this particular disposition, also reduce to more
capacities. Problematically, any time we are confronted with a property, it reduces to a
capacity, and any time we are confronted with a capacity, it reduces to another capacity.
Because every capacity reduces to a reducible capacity, we have an infinite regress. So we
need qualitative properties in our analysis of property identities.
Now let us examine the manifestation of dispositions. According to the pure powers view,
when a disposition manifests, there is no manifestation of a qualitative property. The
manifestation is merely another causal power (or a collection of causal powers). And when
this new casual power is manifested, it will also merely be manifesting another causal power.
Martin writes, “this image appears absurd even if one is a realist about capacities—
dispositions. It is a promissory note that may be actual enough, but if it is for only another
promissory note that is [for another promissory note, and so on], it is entirely too
promissory” (Martin 2008: 63). The purely dispositional account does not allow that a real
thing happens in a manifestation (I mean something beyond its gaining the power to cause
something else); a manifestation is merely a promissory note. By this, Martin means that we
receive a promise that, although the manifestation was not what we expected, some real
event—the new dispositions—will lead to an eventual manifestation that we expect. In other
words, the causal potentiality that the object acquired may lead to causing a real something to
happen. However, each new disposition is only a disposition for gaining or losing dispositions
(see Martin 2008: 61-63). Therefore, a world of dispositions is a world of mere potentialities.
All that happens is the introduction or loss of potentialities.
Perhaps the above reasoning is unconvincing to one who is already a pure power theorist. My
hope is that it gives some reason to deny the elimination of qualitative properties. But now it
seems that we face a dilemma: on the one hand, positing qualitative properties as
ontologically distinct from dispositional properties leads to epistemic worries; on the other
hand, eliminating qualitative properties seems absurd. The identity theory is a way between
these two unpalatable options. In asserting that properties are simultaneously dispositional
and qualitative the identity theory avoids the epistemic worries arising from positing
qualitative properties as distinct from dispositional properties.